Pumping jack for oil wells



Jan. 19, 1932. D. K. CASON. JR 71,841,712

PUMPING JACK FOR OIL WELLS Filed Jan. 12, 1925 2 Sheets-Sheet 1 5 atfcnm Jan. 19, 1932. D. K. cAsoN, JR

PUMPING JACK FOR OIL WELLS Filed'Jan. 12, 1925 2 Sheets-Sheet 2 Patented Jan. 19, 1932 NETE DICK K. CASON, JR., OF NACOGDOCHES, TEXAS PUMPING JACK FOR OIL WELLS Original application filed April 10,.1924,.Seria1 No. 705,446. Divided and thisapplication filed January 12, 1925. Serial No. 1,833.

10 be converted into a straight line vertical motion of the pump rod thus avoiding vibration or friction in the said rod.

It is also desired to provide a jack for pumping wells that may be arranged to take 15 up a minimum of space on the derrick platform in use and to be collapsed out of the way when not in use. This application is a division of the subject matter disclosed in my copending application, N o. 7 05,446, filed 2 April 10, 192%, which has resulted in Patent 1,579,514, dated April 6, 1926, on an improvement in jacks for pumps and the like.

Referring to the drawings, Fig. 1 is a top plan view of my invention applied to asec- 25 tion of derrick platform. Fig. 2 is a side elevation thereof showing the platform and guide in section. Fig. 3 is a section transversely of the guide, as shown in Fig. 2. Fig. 1 is a view similar to that shown in Fig. 2

1 so of a slightly differentembodiment. Like numerals of reference are employed to designate like parts in all the views.

In the drawings the numeral 1 is employed to designate generally a derrick platform of the usual construction resting on the usual sills. Transverse parallel joists 2 are spaced apart to furnish the support required for my improved jack.

The well is represented as having a tubing 40 3 projecting slightly above the derrick platform and having a polish rod 5 working through a stufing box therein.

The pumping jack comprises a walking beam 6' which is not of the usual walking beam construction, but comprises a straight bar, the forward end of which is provided with spaced arms 7, oneon each side thereof to straddle the polish rod 5, each arm or bracket 7 is provided with a curved recess Q 8 on its upper face to receive across-pin 9 formed on a sleeve 10 secured to the polish rod. It is contemplated that the weight of the rod 5, and the pump plunger connected therewith, will hold the cross-pin 9 firmly seated in the recess 8, as shown particularly in Fig. 2. The beam is pivoted upon axis 11 which is itself secured between supporting le 's 12, one on each side thereof.

The said le s 12 are pivoted at their forward ends at 13 to a shaft extending across from one joist 2 to the other, as shown particularly. in Fig. 1. This shaft is spaced slightly toone side of the well casing so that the upper end 7 of the walking bearnprojects beyond the pivotal point of the legs 12. The upper ends-of the said legs are provided with brackets 14.- which extend upwardly at right angles to the legs and are pivotally connected at 15 to a pitman 16 which acts to connect thelegs operatively with a crank pin 17 upon a crank arm 18. Said crank arm is secured to the shaft 19 having a bearing at20 positioned at one side of the walking beam, and maybe rotated through some source of power, not shown.

The lower or rearward end of the walking beam 6 is formed with an opening therethrough to receive a shaft 21 upon each end of which is formed a roller 22 adapted to roll upon a track 23 in the guideway 24 or 24'. is shown in Fig. 3, the rollers 22 have an inner flange 25 which fits against the inner faces 26 of the guideway, thus holding the lower end of the walking beam firmly in the rack 23, and preventing any lateral movement thereof. The guide .track 24 is curved on ,a slight are so as to allow for the movement of the forward end 7 in a vertical line, but may be inclined as in Fig. 4 or horizontal as desired .to meet the existing conditions. As shown in Fig. 2, the track is closed by a wall 27 at its rearward end and is open at its forward end to allow for the removal of the beam 6 from the rollers when occasion arises.

In the operation of the device, when the walking beam 6 is reciprocated through means of the crank arm 18., the pitman 16 and the pivoted supports 12, the forward end 7 thereof will be raised and lowered in an obvious manner to reciprocate the pump rod. The lower end of the beam being supported upon the rollers 22 so as to be movable as the beam is raised and lowered, the construction will allow the forward end to move in a straight line vertically above the casing 3 of the well. When the upper end of the stroke has been reached, the load supported upon the pump rod will tend to cause a sudden drop of the walking beam on its downward stroke. To overcome this abrupt movement which acts to cause a jar upon the moving parts, I may provide a counter balance spring 28. Said spring may be a heav coil tension spring, the forward end of which is preferably secured to the shaft 13, and the rearward end of which is secured at 29 to an eyelet on the lower side of the walking beam 6. This spring will tend to assist in the upward movement of the pump rod, and resist its downward movement, thus acting in the place of the usual counter-balance weight employed on the old type of walking beam.

The action of the spring is believed to be superior, however, to that of the counterweight, in that its strongest resistance to the downward drop of the pump rod occurs when the said sprin is extended at the lower end of the stroke 0% the plunger, and that its least resistance is at the upper end of the stroke. The greatest resistance occurs at the point where the sudden jerk is ordinarily experienced and will hence tend to resist the sudden movement at the point Where it ordinarily occurs. The spring is hence most eflective at the point where its use is most desired. It will also be noted that the tendency of the rear end of the walking beam to be moved upwardly when the beam is operated will be resisted by the upper portion of the track shown at 30 in Fig. 3. There will therefore be a lifting movement upon the track 24 at the time when the weight of the Walking beam is supported upon the derrick platform through the legs 12. The two movements will counteract each other to a slight extent, thus tending to place a smaller weight upon the frame of the platform than would ordinarily be ex erienced with the usual type of pumping jack.

It will also be noted that the forward pivotal point 13 of the supporting post 12 is placed at a point below the upper level of the platform. Furthermore, the platform is cut away, as shown at 31 to allow the walking beam 6 and the supporting post 12 to drop downwardly in collapsed position below the level of the platform when the device is not being operated. This may be done'by releasing the pitman and the supporting posts from their connection with the crank arm 18 and dropping the forward end of the walking beam downwardly so that the arm 7 will rest in the platform at each side of the casing out of the way.

In carrying out the inventive idea of the improvement, the structure may be modified as shown in Fig. 4. Here the walking beam 6' is formed with its lower roller movable on a guide 24 which is straight but may be inclined downwardly toward the rear. This allows me to support the post 12 at 13 beyond the well casing 3 from the said walking beam.

To better accommodate this construction, the olish rod 5 is connected with the forwar end of the walking beam through a short cable 36. The forward end 37 of the said beam is curved, as shown, to provide for the attachment of and vertical movement of said cable.

The arms 14' to which the cable is attached are preferably lengthened and may be integral with the posts to which they are secured. This allows a longer lever arm in the operation of the device through the pitman and also places the point of connection 15 at a more advantageous angle relative to the crank arm. For it will be noted that the point 15 in this embodiment cannot so nearly approach the dead center position sometimes assumed in the previous design.

In the Fig. 4; embodiment, I have also illustrated the use of a counter-balance weight 34 to take the place of the spring 28 shown in the other form. This weight is secured at the forward end of the beam 33 pivoted upon the shaft 13'. It is connected by cables 35 to the u per ends of the posts 12 as shown. The weig t thus acts to assist in raising the pump rod on the upward stroke, and in resisting the sudden drop thereof on the downward stroke. The said beam 33 and weight 31 will collapse into the space below the derrick platform when disconnected from the post 12' in an obvious manner, so as to house the complete jack below the platform when not in use. Thls is a most desirable object, not capable of accomplishment by devices now commonly use This jack may also be operated b a power unit directly upon the derrick plat orm servmg to actuate a pitman connected directly with the jack itself. It will also be noted that, in the operation of the shaft 19 to turn the crank arm in a circle in a direction shown by the arrow, the crank arm will be in a most advantageous position when the load of the pum rod and fluid is being lifted. Also, on the ownward stroke, it will be pulling in a direction most nearly in direct opposition to the direction of the cable 35 connecting the counterbalance to the arm 14. This is also of material advantage.

It will therefore be understood that the device is simple and compact in its arrangement and that it will not be in the way when it is necessary to handle the tubing or the sucker rod in withdrawing the same from the well, as occasion requires.

Further objects and advantages of the invention will be apparent to those skilled in the art. What I claim as new and desire to protect by Letters Patent is:

1. In a device of the character described, an inclined walking beam, a swinging post pivotally supporting said beam intermediate its ends, an upwardly extending arm on said post, a guide in which the lower end of said beam is movable, and means connected to said arm to reciprocate the upper end of said post whereby the said upper end of the beam is moved in a vertical direction.

2. In a device of the character described, a platform, a beam secured at its upper end to a pump rod and inclined downwardly at its other end, a guide for said lower end, swinging posts pivotally connected with said beam between its ends, and means to swing said posts and move said beam, said posts and beam being supported below the level of said platform and adapted to collapse below said platform, as described.

3. In a device ofthe character described, a walking beam, a swinging post upon which I said beam is pivoted, one end of said walking beam adapted to engage a pump rod, means to restrain the other end of said walking beam from excessive vertical movement, a counterbalance on the opposite side of the well from said walking beam connected to resist the downward movement of said pump rod.

4. In a device of the character described, a walking beam, a swinging post upon which said beam is pivoted, a shaft about which the lower end of said post is pivoted, a counterbalance beam also pivoted about said shaft, and connected with said post to resist rearward movement thereof.

5. In a pumping jack, a beam for operating a polish rod, a movable support for said beam, means to restrain the end of said beam opposite said polish rod from excessive vertical movement, and means tending to resist the downward movement of said polish rod.

6. In a device of the character described, a base, a walking beam, a swinging post pivoted to said beam and to said base, a detach able means to move said beam, said beam and said post interfitted so as to collapse.

7 In a device of the character described, a beam adapted to engage a load at one end, means to restrain the vertical motion of the other end of said beam, a swinging post supporting said beam between its ends, means to reciprocate the upper end of said post comprising a pitman and a crank whereby the load engaging end of said beam is reciprocated in a vertical direction.

In testimony whereof I hereunto affix my signature this 3d day of January, A. D. 1925.

DICK K. OASON, JR. 

